Lithuania, Latvia and Estonia are racing to find replacement air filters after public agencies and suppliers reported a sudden shortage, triggered by warnings that Katla could erupt within days. Scientists monitoring the Icelandic volcano say a burst of shallow earthquakes, ground uplift and rising heat beneath the Mýrdalsjökull ice cap has sharply increased the risk of an eruption before the end of October.
The three governments’ combined reserve of 82,000 P3 filter cartridges for public shelters has fallen to 19,400 usable units, according to figures shared by the Baltic Civil Protection Coordination Office on Saturday. One large supplier in Riga said it had no stock left after orders jumped sixfold in 24 hours. Officials urged people not to buy filters for home use.
Key facts - 4,800 shallow earthquakes recorded near Katla in 72 hours - 19,400 usable cartridges remain in Baltic public reserves - Scientists’ highest-risk window runs through 2 November - Baltic officials will review stocks on Monday
Signals build beneath the ice
The North Atlantic Geoscience Centre said sensors recorded 9cm (3.5in) of uplift over two days at a station near the glacier’s southern edge, alongside a marked increase in shallow tremors. Its latest wind models show that, if a high ash plume forms, material could reach the Baltic region in 36 to 60 hours. Three of 12 model runs put ash over the region.
The pattern has shifted from something we watch to something we prepare for.
Olegas Kotryna, seismologist at the North Atlantic Geoscience Centre
Kotryna said the centre estimated a 25% to 35% chance of an eruption within seven days, an unusually high figure but not a prediction that one will happen. A large eruption could send ash 12km to 15km (7.5 to 9.3 miles) into the atmosphere, disrupting flights across northern Europe and leaving a thin layer of ash in parts of the Baltic states. The most likely outcome, he said, remains no eruption in that window.
Shortage turns into a political row
Baltic officials have tried to lower the temperature. Anelė V. Žygaudas, Lithuania’s deputy director of civil protection, said the current forecast did not justify closing schools or telling residents to shelter indoors. “We are preparing for a possible disruption, not announcing a disaster,” she said, adding that governments were checking public buildings and seeking replacement filters from suppliers in Finland and Poland.
That message has drawn sharp criticism from opposition lawmakers and mayors in coastal districts, who say the public was reassured too quickly. The dispute has taken on the edge of an election campaign, with one side accusing ministers of alarmism and the other charging them with downplaying the scientists’ warning. Brian Pedersen, who heads the Baltic Filter and Ventilation Guild, said commercial stocks could not cover a sudden regional demand surge.
Airlines have not changed schedules, and aviation authorities have issued no closure notice. Still, the North Atlantic Ash Desk has asked carriers to prepare alternate routes if a plume develops. A disruption lasting several days could affect flights, freight and time-sensitive deliveries; officials in the Baltics say hospitals and water-treatment plants will receive priority if filters have to be rationed.
The three governments are due to compare stock figures on Monday and decide whether to make a joint purchase. Iceland’s monitoring teams are also checking meltwater channels below the glacier, where an eruption could send sudden floods toward nearby valleys. The Baltic states face no volcanic flood danger, but researchers say the next 48 hours of readings will determine whether the ash warning moves from planning scenarios to active precautions.
